A few weeks back I rasied a trheard about AlKo Flange nuts ..... https://www.rib.net/forum/f49/sbs-tr...uts-85347.html
Went ahead and did service - detsuils beklwo may be of use to some.
New boat and trailer halfway through last season, so with only 20Hrs use expected brake service to go easy, to be I was wrong.
The trailer is an SBS 2600 EL and been happy with the way it performs, recovers well, and tows a treat, some nice touches such as built-in wiring to the lights, hub-flush, nylon mudguards (better than Galv that rust & split easily) and chassis is one piece - all welded together prior to Galvanising.
Time for maintenance
First off could not get the dust caps off the hubs, they do not come off easily or without damage .. a rubber mallet, pipe grips etc.
So had a copy of the removal tool made up in a lathe :
Works a treat removes and refits with zero damage.
The flange nuts were really tight .... I loosened with a 1m long torque bar to beak the seating and then removed them with a pneumatic air driver.
Now the unwelcome part ... You can see the corrosion of the brakes after on a few months use, and worrying was the rust on the swing-arms.
Stripped all parts out, degreased fully, then De-Salted with CHLOR-X, rinsed off. Cleaned inside drums with WURTH drum cleaner
The stub axle, main cross axle swing arms had significant rust on them …after only ½ a season …. It is bsurd that Alko produce galvanized cross-beams, back plate, but the swing-arms are just pained with a thin matt black paint, the stub axle inside the drum is not painted at all ……. Both corroded significantly.
Also the brake shoes are only electro-plated not galvanized .. so they rust after the first dip in the sea.
Treated all rust with KuRust Rust converter.
Painted swing arms, drum, shoes and stub axle …… using Rust Buster EWM21 2-part epoxy paint … this stuff is 100% salt waterproof, and hard as nails.
I reassembled the brakes, and it's worth saying that AlKO excels at making it difficult to refit the shoe spring retaining clip ….. one side is easy, the other is between the swing-arm and back-plate , with less than ½” gap …. You can’t get a finger in there, let alone with a clip….. poor design.
I ended up compressing spring with a clamp and lowering in the retaining clip with a telescopic magnet. It should not be this difficult.
Before fitting the drums sprayed the backplate, springs, adjusters with Lanoguard marine & chassis liquid …. and coated adjuster mechanism in Lanoguard Marine grease.
Also sprayed the liquid on the rear of the back-plates.
This marine spray product sprays on easily then set like a wax coating, a bit like Waxoyl if you are familiar with that ...... but much superior performance
I had masking tape on the contact face of the shoes, and also did not spray on the inside of drums.
Putting the drum back on with new flange nuts is a new experience
, always had taper roller bearings previously you install with end float and a split pin. These 'Euro hubs' use ‘sealed for life bearings and these are fitted with a one-time use flange nut, which you have to discard each time you remove, and they need to be torqued to 290 Nm, this was outside the range of my torque wrench …. Luckily picked up a big beast of a torque wrench off off Market Place.
To reach 290Nm still need a long piece of tube over the torque wrench handle ….. it’s a lot of torque
Not sure I like the idea of no seals on the bearings …. I know they are classed as ‘sealed for life’ but that may work on a caravan, but being fully immersed in Saltwater each time I go out ….. can’t see them lasting too well. On another forum guys are talking on replacing after 18 months .... my Taper roller bearing were still good after 5 years - just replaced seals annually. On the Tape Roller bearings I used to fit Bearing Buddies which kept a positive pressure on the grease. Did keep bearings good, but due to seal leakage, the backplates were really messy when it came to annual service.
Job done for this year ... Lanoguard suggests spraying the whole of the trailer ... not sure if I will do that, but will apply oil to all moving bits and all the nuts & U bolts.